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تسجيل مستخدم جديدBeppoSAX observation of NGC 7674: a new reflection-dominated Seyfert 2 galaxy
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تأليف
G. Malaguti
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The Seyfert 2 galaxy NGC 7674 has been observed within the BeppoSAX Core Programme with the onboard narrow field instruments between 0.1 and 100 keV. The broad-band spectrum shows four most relevant spectral components: a) a soft excess below ~2 keV; b) a prominent (EW~1 keV) Fe line; c) a flat (Gamma~1.1) 2-10 keV continuum; d) a 4.5sigma detection above 13 keV. The flat power law spectrum can be very well explained within the current AGN unified models assuming a steep (Gamma~2) intrinsic spectrum scattered by warm gas for the low energy band and totally reflected by optically thick cold matter (plausibly a molecular torus) for the high energy band. The case of NGC 7674 adds to the increasing number of so called Compton-thick Seyfert 2 galaxies in which the direct emission is totally absorbed and the X-ray luminosity is thus at least one or two orders of magnitude larger than what inferred from the observed flux.
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